Switch box



Oct. 15, .1940.

A. W. THOMASEN SWITCH BOX 2 Shams-Sheet J.

Filed Dec. 28, '1935 INVENTOR ALFRED W. THoMAssN,

BY 7 I WATTORNEY Oct. 15, 1940.

A. W. THOMASEN SWITCH BOX 2 Sheets-Sheet 2 Filed Dec. 28, 1935 INVENTORALFRED W. THouAssn',

TTORNEY Patented Oct. 15; 1940 PATENT OFFICE 2,218,033 swrrcn BOX AlfredW. Thomasen, Plainville, Conn., assignor to The Trumbull ElectricManufacturing Com-. pany, Plainville, Conn., a corporation ofConnecticut Application December 28, 1935, Serial No. 56,403

1 claim.

One object is to form a rectangular roundcornered sheet metal boxsuitable for enclosing an electric switch.

Another object of my invention is to provide a strong round-corneredrectangular box which can be made of relatively light metal.

Another object is to form a suitable roundcornered box at a minimumcost.

Another object is to form such a box with a minimum waste of materialand without requiring the use of extremely powerful drawing mechanism.

Another object is to so construct a switch box that it will have aminimum of exposed joints.

In its preferred form the box is made of three pieces of sheet metal,the body having a bottom piece welded to the flanges of a single stripforming the sides and ends and the cover stamped and shaped to fit theinset edges of the body. an Fig. 1 is a perspective view of a switch boxembodying my invention.

Fig. 2 is a side View and partial section showing in dotted lines, ahinge.

Fig. 3 is a broken plan view of the bottom of 25 the box.

Fig. 4 is a broken view of the blank from which the sides and ends areformed.

Fig. 5 is a broken plan of the body of the box.

Fig. 6 is a fragmentary section of the joint between the ends of theblank which forms the sides and ends of the body of the box, the sectionbeing taken on the plane of the line 6-6 of Fig. 2.

The box has a body l0 and a cover I l preferably hinged to the body at"l2, the edge of the body being notched as shown in Fig. 2 to allow forthe hinge. A latch l3 and handle H are usually provided and a handle i5for actuating the switch. The box must be deep enough to contain theswitch mechanism and strong enough to withstand the strains to which itis subjected.

The body of the box is formed of a bottom plate l6 and a side strip llcut and formed as shown. The corners iii of the bottom plate it are cuton a ninety degree (90") are and the edges of the strip ii are notchedat 19 and 20 to form lugs 2i, 2! and to leave flanges 22, 22.

These lugs and flanges are bent over at right angles to the plane of thestrip and the strip is bent to the shape desired. The lugs and flangesare then welded or riveted to the edges of the bottom plate.

One end 23 of the strip i1 is oifset from the adjacent metal and weldedor riveted to the opposite end 24 as shown in Fig. 5. The edge of thebottom plate is cut or notched at 25 to allow for the seam formed by theoverlap of 23 and 24.

The edge of the body is inset at 26 to allow for the flange 21 of thecover so that the edge of the cover is substantially flush with thesides and ends of the body.

The cover I I may be bossed as indicated at 33.

It is, of course, possible to form a round-cornered box by stamping ordrawing from a single sheet of metal but this is a very 'expensiveprocess iii and requires the use of expensive metal and machinery. Themethod I have used makes it possible to use cheaper metal and lessexpensive dies. It also makes it possible to use a difierent kind orgageof metal for the bottom which must support the base of the switch.

It will be seen that the joints between the bottom and the sides andends are entirely concealed from external view when the switch is in useand that the joint overlap 23, 24 is partially concealed by the coverwhen closed. The box is therefore neat and attractive in appearance.

I claim:

A round-cornered switch box made of a rectangular sheet metal bottomplate with rounded corners, said plate having a notch in one edgethereof, a single sheet metal side strip of a length greater thanthe-perimeter of said plate, one edge of said strip having a pluralityof notches at spaced points corresponding to the location of the roundedcorners or the sides of said plate, said strip closely surrounding theedges of said plate and said notched strip edge being bent Linder andoverlapping the edges of said bottom plate, one end of said strip, whereit is necessarily overlapped by the opposite end, being onset inwardly adistance equal to the thickness of the material of said strip,.,saidoiiset portion entering the notch in the plate edge, said overlappedstrip ends and said overlapping strip edges and plate edge being firmlysecured together.

ALFRED W. THOMASEN.

